Lise - just reread your post and noticed you mentioned shields. I used them for a couple of weeks because of bad attachment due to a tongue tie. I started them at about 5 weeks though I think. I found it hard to believe that he would attach without them but eventually he did after a couple of days of weaning him off them. Also their attachment improves as time goes on and they get bigger (even with flat nipple) so you may not have to use them forever if you are unhappy with them.